NERVOUS SYSTEM

in #steemstem7 years ago

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When an athlete accidentally falls on or step on sharp object, he or she feels the pain and quickly respond to it by jumping up. The response is a result of the stimulus generated by the foot. Thus, the body responds to stimulus by the help of nervous system.

   Message are carried as electrical impulse along nerves which immediately responds from the target organ.

      COMPONENTS OF THE NERVOUS SYSTEM

The basic unit of the nervous system is the nerve cell or neurone. The neurone consists of collection of dense cell body known as nerve fibre(nerves). The nervous system consists of;

  1. The brain.

  2. Nerve that brings information to the brain from the receptors (information collectors).E.g. Nerves found in the sense organs, eye,skin,ear,tongue,and nose.

  3. Nerves that carry instruction from the brain to effector.E.g. nerves found in muscles and glands.

     The nervous system carries information and instruction almost immediately.
    

    ORGANIZATION OF NERVOUS SYSTEM
    The nervous system is made up of the following;

  4. Central nervous system.(CNS)

  5. Peripheral nervous syatem.

1.CENTRAL NERVOUS SYSTEM:
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The central nervous system consist of the spinal cord and brain. It also co-ordinate the activities of the nervous system. Impulses to the CNS to the effectors are known as motor impulses.
SPINAL CORD
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The spinal cord consists of thousand of neurones. It runs from the brain down the reflex action.
FUNCTION OF THE SPINAL CORD

  1. It co-ordinate simple reflex actions E.g.knee jark, sweating.
  2. It acts as a pathway between the spinal nerves and the brain
  3. It relay impulse to the brain.
    The spinal cord contains cerebral-spinal fluid. This fluid is a clear colourless fluid.

THE BRAIN
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The human brain consist of three main parts namely. The cerebrum, the cerebellum and medula oblongata.

The brain is divided into three;

  1. The fore brain
  2. The midbrain
  3. The hind brain

The fore brain is the site of intelligence and speech. These include the cerebrum, thalamus, and hypothalamus. image

CEREBRUM

Cerebrum is the first division of the human brain. It is the largest division of the human brain. It fill upper part of the skull. It thinks and feels, decided what individual will do and govern the whole body. It is the centre of memory, reason , reason and good judgement. It is also real origin of human personality, which makes human being different from other mammals. 

FUNCTIONS OF CEREBRUM

  1. It co-ordinate all the body's voluntary and involuntary activities.

  2. It receives sensory information, process it and send the instructions to the effectors neurons for action.

  3. It is the seat of intelligence.

FUNCTION OF THALAMUS.
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1. Receives sensory information from various part of nervous system and send it to the cerebrum.

 2. It controls endocrine secretions. 

MIDBRAIN
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This is a region that connects the fore brain with the hind brain.
function: controls certain reflexies connected with sight and hearing.
HIND BRAIN
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The hind brain co-ordinates most of the body autonomic involuntary activities. The hind brain is composed of the three parts namely;
-the cerebellum
-the pons varolii
-**the medulla oblongata **

  1. The cerebellum is located at the back lobe of the cerebrum. It assists in controlling muscles of locomotion, balance and equilibrium.
    function it controls and co- ordinates body posture and muscular movement that maintain body balance. image

  2. PONS VAROLI bands of fibre that joins the cerebellum. image

  3. MEDULA OBLONGATA medula also has centres that controls the heart and lungs. Death occurs whenever the medulla is injured. The heart stops beating and breathing stops too.
    functions of medulla oblongata.
    I. it controls many involuntary movement of the body especially those concerned with respiration, heartbeat and digestion.
    II. It also controls contraction and relaxation of blood vessels.

       Their are more to the nervous system than we can evenly  imagine. 
    
            **facts about the nervous system**
    
  4. Sodium ion and potassium are the building function to the nervous system, Without its presence it's impossible to function(nervous system ).

  5. Hmm, fascinating. 6.5 more gray matter in men than in women,but. The woman brain has 10 times more white matter than in man.

  6. Their are about 14,500,00 neurons in the human spinal cord.

  7. Their are over 999.9 billion neurone in the human brain alone.

  8. Also the central nervous system helps the body communicate with each other.

       The brain is a very delicate object as theirfore should be protected with care. The brain stores vastly zillions of information without running low. Indeed, more efficient than a computer. It aids thinking and even what we all are yet to understand dreaming. Take good care of your mind. 
    
    Hope you love this insightful whrite up  don't forget to upvote and comment thanks.